Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Conversion of restricted stock units to common stock, treasury shares purchased	140,592	146,999	71,112
Convertible debt extinguishment impact, tax impact	$ 564	$ 5,498
Tax impact of 2036 Senior Notes conversion liability reclassification			$ 18,025
Treasury Stock | Stock appreciation rights
Settlement in common stock, treasury stock purchased (in shares)	14,367	62,866	35,955
Treasury Stock | 2019 Convertible Debt
Settlement in common stock, treasury stock purchased (in shares)	1,902,781